Jay Sean is back in the U.S. after a brief promotional trip through the U.K. While back in his home country, he caught Cash Money Records labelmate and recently ranked #2 Hottest MC in the Game, Lil Wayne, performing on his home turf in London. Sean told us about visiting with Wayne after the show in the privacy of his double-decker tour bus.

"It was just me and him," Sean recalled. "I said, 'You know what, bro — thank you. You made a dream come true for me. I got ... well, we have a #1 record in America.' And he just did his legendary laugh and was like, 'Yeah, man! That's what's up!' "

The cause for celebration? His single that features Lil Wayne has put an end to the Black Eyed Peas' six-month-long domination of the #1 spot in popular music. "Down" has replaced "I Gotta Feeling" at the top of the Billboard Hot 100. The BBC has dubbed Sean "the most successful male U.K. urban artist in U.S. chart history." Not bad for a guy who has yet to release his debut album in the States.

"When I heard the news I was in London, about to do an interview for radio. It's been the only time in my career where when I found out, I literally couldn't breathe properly. I was so excited. I was so happy," Sean gushed.

Remarkably, Sean's single has taken over U.S. radio even though the star himself has been flying under the radar, avoiding making headlines or becoming fodder for gossip blogs. To this day people are still figuring out just who he is, although that's changing — quickly.

"The video is getting a serious amount of airplay and with that people are starting to recognize me, but again, America is so huge, so we still have work to do," Sean said. And while it may be simple to chalk his success up to beginner's luck, it seems unlikely. After all, his upcoming album will in fact be his third (his two previous platinum-selling albums were released in Europe and Asia).

A simple glance at his Twitter page and you'll think he's been Stateside for years: You'll see kudos from Ashton Kutcher and Chamillionaire, Keri Hilson reprimanding him for not showing more of his bare chest in the "Down" video and musings from Lil Jon about having just recorded a club banger with Sean, the album's second single, "Do You Remember."

And so with the combination of determination, chart success and industry backing, it now seems that Jay Sean should be prepared to wave goodbye to anonymity. His debut album, the aptly titled All or Nothing, hits stores November 24 — and for the former medical school student, it's the culmination of everything he's worked for.

"I love music with such a passion," Sean said. "I do it because I want it all. I want to take my piece of work, which I'm proud of, and I want to take it as far as I can take it. Otherwise I don't want any of it."